WASHINGTON (AP) – The government says nearly 1 in 5 drivers in the U.S. is over 65 years old, thanks in part to the aging baby boomer generation and greater longevity overall.

Preliminary data from the Federal Highway Administration also show there are more drivers today than ever before, an estimated 217 million.

Drivers over 65 are one of the fastest-growing demographic groups among U.S. drivers, increasing 2 percent last year. That’s the biggest single-year percent increase on record that population, and represents 4.4 million additional older drivers.

The number of teen drivers increased slightly in 2015 for the first time in two years, rising to 8.73 million from 8.5 million in 2014, but continuing to remain at a near-record low. By comparison, there were nearly 10 million teen drivers in 2008.

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